Origin

Water, shown by the three-drop radical on the left, combines with a sound hint on the right that suggests the pronunciation "taku." A swamp or marsh is a wetland where water pools and collects, so the water radical makes sense for the meaning. The same character also came to mean brilliance and grace, likely because smooth, calm water reflects light beautifully and suggests elegance. The right component is purely there to hint at how to pronounce it, not to add to the meaning.